If you don't know this plant, its a member of the Apocynaceae which was already one of my favorite families before it subsumed the Asclepidaceae, which I liked even better! Adenium is a caudiciform plant (it grows from a swollen base) that can grow to a height of over 5'. On a plant that size the base would be 1-2' in diameter making a quite impressive specimen. It looks sort of like an upside down green turnip with multiple branches tipped with glossy evergreen leaves. The flowers occur throughout the year for me; it's more often in flower than not.
Sometime in the late 70s or early 80s, this plant broke away from the specialists and collectors and began to pop up in garden centers and nurseries. The flowers on those first plants weren't so sharply bicolored as this one. As spectacular as these flowers are, they pale in comparison to other varieties; Bob Smoley's Gardenworld lists, regularly from 5-10 named selections and he likely has at least that many more not listed. Still haven't visited their new location which is about 15 miles from the Florida Garden. Maybe this July.
You might think that in Zone 9 there would be enough hardy tropicals so that tender houseplants wouldn't appeal to a lot of people, but there must be something about this plant....At flea markets there are often entire vendors who carry nothing but Desert Rose and it's common in nurseries and box stores. This plant was about 1 1/2' tall and cost 5$ and we brought it north!